Oh sure, it's crammed to the gills with information, but it's so poorly written that the lumps of information sit on the page like rocks in a river, slowing the flow.
For instance, in an early part of the book, the protagonists are racing through the Tuileries in Paris. Despite the fact that the Tuileries play no part in the workings of the plot, Brown feels it important enough to stop the action and leadenly dump into his prose an explanation of the name "Tuileries".
It's like that all the way through. People suddenly find themselves, even in the most dangerous moments, being "reminded" of yet another irrelevant fact or other.
I thought at first that it was quite a page-turner, but eventually I found myself yearning for the end to come. I really need to shake off this feeling of having to finish a book, just because I've started it. Life's too short and there are more than enough good books to read.
If you want to read about the Merovingians, the Knights Templar and the conspiracies surrounding Mary Magdalene and the Jesus bloodline, look out a copy of Henry Lincoln's Holy Blood - Holy Grail.
Although not an especially good book, I got more out of an hour reading Rhino Ritz: An America Mystery by Keith Abbot, which contains the following:
F. Scott Fitzgerald was trying to put his arm back on. It had fallen off in the street and he was trying to put it back on so he could drink some more. It was his right arm and he needed his right hand to drink with.
A bizarre concoction written by someone I've never heard of, it's strangely reminiscent of William Kotzwinkle or more nearly, Richard Brautigan.
And whatever became of Richard Brautigan?
Apart from being dead, that is.